The success, to date, of fossil fuels being able to meet energy demand any time required has led to a feeling of society wide unrealistic entitlement. This translates into a belief that whatever we want we can always have whenever we want it. This of course is leading to problems as it patently can no longer be maintained. It also has lead to the development of quite unrealistic expectations as to how far renewables can replace fossil fuels.

Renewable energy is being tagged on to a massive existing demand led fossil fuelled energy system that has historically grown and grown. Attempts at demand reduction and increased efficiency seem to deliver slim savings and these are often cancelled, for example, by people choosing higher comfort levels or just doing higher milage in their more efficient cars.

For a number of years I worked for a company supplying small (20 – 100 kW) wind energy systems. The company failed and went bankrupt mainly because of a lack of investment and a very low profit margin on sales, certainly not for want of potential customers. Apart from that it was great fun and a hugely important part in the development of my understanding of the practical limits of renewable energy.

I spent a lot of time travelling to sites ranging from Shetland and the Western Isles in Scotland to the south coast of England, commissioning and servicing wind turbines. It was amazingly easy to run up huge mileage and fuel consumption moving tools equipment components and myself, even in an economic diesel estate car. This was what first gave me the clue as to the limits that would apply to renewable energy trying to replace fossil fuels and to the dependence of renewable energy on a continuing fossil fuel platform to operate.

It is natural to attach much importance to an area in which you have devoted a significant proportion of your working life and hopes for the future. It is hard to admit fulsomely that, on mature reflection, a lot of it does not stack up or really be sustainable in a future minus easy oil and the abundant easy availability of raw materials. Let us consider Ireland as an example.

Ireland’s total energy use in 2008 amounted to about 16 Million Tonnes of Oil Equivalent (TOE). In 2008 renewables produced about 0.6 Million TOE which is only about 4% of total energy use. This is another way of saying that all the renewable technology presently installed has only made us 96% fossil fuel dependent rather than 100%! This should give us a worrying clue as to the very extreme degree of energy descent that may be experienced as we move further into post peak oil. Achieving any really significant percentage of renewable energy contribution to current consumption levels appears to be next to impossible. Current efforts to try and achieve this impossible target require ever more massive and complex machinery and higher and higher inputs of, increasingly scarcer materials and fossil energy to achieve.

The point is very simply that an enormous amount of fossil energy is required to manufacture, install and operate all forms of renewable energy systems. Without the input of fossil fuel the existing renewable energy projects could never have been built and could not be maintained in operation.

All these systems are manufactured in largely fossil-fuelled factories employing tools, equipment and components produced in other fossil fuelled factories. The raw materials and components used require energy intensive extraction and fabrication techniques to produce, and along with the finished products, also have to be transported substantial distances, often by road.

The workforce probably largely travels to work by car and also frequently flies around the world to the sites where their products are utilised. I would be very surprised if the managers in these companies do not drive large, shiny, status enhancing motor cars, live in large houses on car accessed exclusive executive estates and drive and fly to lots of meetings, conferences and exotic overseas holidays.

A trip to any site where, for example, a wind farm is being installed, demonstrates this clearly. There you will find an abundant selection of fossil-fuelled giant earthmovers, cranes, cars and trucks in use. In addition enormous low loaders will be coming and going delivering massive mechanical parts, towers, nacelles, generators, gearboxes, transformers, power cables and blades from hundreds or thousands of miles away.

I have even seen cases of parts and a personnel being transported to remote wind energy sites by that most ridiculously fossil fuel hungry means of transport, the helicopter.

After the wind farm is installed and commissioned, and all the factory personnel have finally flown home, there is then the not so small matter of the continuous operation and maintenance (O&M) required throughout the life of the project to keep the show on the road. Here the fossil fuel energy intensity is reduced but there are still interminable attendance’s on site required to test, tweak, adjust, replace, repair and reset along with the transporting and supply of consumables and spare parts. Once in a while there will be a major spike in fossil fuel intensity when there is a failure of a major component such as a gearbox, generator or a damaged blade needing repaired or replaced.

In addition wind farms are now recognised as mostly having a negative effect on local resilience other than financially benefiting a very small group of people. By siphoning capital out of the area, and often out of the country where they are installed and, by hogging existing grid capacity they preclude the development of other more labour intensive renewable energy generation technologies such as bio-mass and anaerobic digestion fuelled systems. The main benefit local inhabitants get is merely the very dubious feel good privilege of looking at the wind turbines with no enhancement whatsoever of local resilience.

Conclusion

I was very sceptical indeed when I first read the pessimistic assessment of the very small prospects of renewable energy in an oil scarce future portrayed by Jim Kunstler in “The Long Emergency”. It is one of those things apparently so obvious when you think about it but hard to accept at first. However the inescapable conclusion is that the sum total of renewable energy capacity will never be much greater than that installed during this one shot age of oil.

It will rapidly become very difficult to keep operational as we move more into the post peak oil period. What can be made remain operational will be chiefly at a very local small scale and probably require much scavenging of parts and improvisation. A huge amount of thought needs to go in to how this might be achieved and to date this matter has received virtually no attention at all from an industry fundamentally locked into the hubris of gigantism and business as usual.

Systems like solar water heating and PV, with no or few moving parts, should be more long lived until they too become unrepairable. However large and complex systems, particularly in remote and environmentally challenging environments such as wind farms, especially off shore, will probably be early renewable energy casualties of the decline in oil supply.

Editor's NotesRoger Adair is a qualified electrical engineer with an MSc in Energy Management from the University of Sunderland and 10 years working experience in the design, manufacture and installation of renewable energy systems.
He also blogs as part of Transition Ireland and Northern Ireland.